Belgium’s new capital gains tax on securities: 10 key points

Following a government agreement reached on 30 June 2025, a bill introducing a new 10% tax on realised capital gains from the sale of financial assets was adopted by Parliament at the start of April 2026.

The information contained in this article, which is intended primarily for Belgian residents, answers 10 questions relating to the implementation of this new tax.

1. What does this tax involve?

This tax applies to capital gains realised as part of normal private wealth management activities in connection with the sale of financial assets for consideration, outside the scope of professional activities.

2. When does this tax come into force?

The tax applies to capital gains realised on financial assets starting 1 January 2026.

3. What is the applicable rate for capital gains tax?

Capital gains realised on financial assets are taxed at a rate of 10%.

4. Who is subject to this tax?

The tax on capital gains applies to all individual Belgian residents subject to personal income tax, as well as to legal entities subject to income tax (non-profit organisations, foundations, etc.), with certain exceptions.

Non-resident individuals and companies subject to corporation tax (whether resident or non-resident) are not subject to this tax.

Taxpayers relocating their tax residence or ‘seat of their fortune’ abroad may, in certain cases, result in taxation in Belgium. However, such a situation must be assessed in light of the applicable legal provisions.

5. What is meant by the term ‘financial assets’?

The concept of ‘financial assets’ applies to financial instruments, some insurance contracts, cryptoassets and currencies, including precious metals such as investment gold.

‘Financial instruments’ refers to listed and unlisted shares, bonds, money market instruments, derivatives, units of undertakings for collective investment and ETFs (trackers). Generally speaking, this concept covers all securities that may be deposited in a securities account.

Branch 21, 23 and 26 life insurance contracts, whether established under Belgian or foreign law, are likewise affected by the new tax.

Some financial assets including pension savings products, group insurance and – generally speaking – all supplementary Pillar 2 and 3 pension products are exempt from the scope of this capital gains tax.

6. How is the capital gains tax calculated?

The taxable base for the capital gains tax corresponds to the positive difference between the price received for financial assets sold and the acquisition value of these assets. Any expenses or taxes are not taken into account in the calculation of the capital gains.

As 1 January 2026 serves as the reference date for calculating capital gains, a ‘snapshot’ of the portfolio’s valuation as at 31 December 2025 will form the basis for calculating capital gains, thereby effectively exempting previous capital gains arising prior to that date.

For financial assets acquired before 1 January 2026, capital gains tax will be calculated on the basis of the positive difference between the sale price and the value of the financial product as at 31 December 2025.

For financial assets acquired starting from 1 January 2026, capital gains tax will be calculated on the basis of the positive difference between the sale price and the purchase price.

7. Are capital losses tax-deductible?

Capital losses realised during the year are deductible and can reduce the amount of capital gains realised solely during that same year, provided that they relate to the same category of financial assets. However, they cannot be carried forward to the following tax year.

In order to claim a tax deduction for capital losses incurred during the relevant tax year, the taxpayer must include them in their tax return.

8. How can I claim the annual tax exemption?

The law provides for an exemption of EUR10,000 per year per person on capital gains. This exemption is indexed annually. It is possible to carry over the balance of the unused first tranche for five years up to a maximum amount of EUR 1,000 per year, thus taking the maximum amount of the exempt first tranche to EUR 15,000.

To qualify for this exemption, the taxpayer must apply for it via their tax return.

9. How is the capital gains tax paid?

For transactions carried out on or after 1 June 2026, capital gains tax is, in principle, deducted at source by intermediaries established in Belgium via the withholding tax system (opt-in).

The government has introduced a transitional period for transactions carried out between 1 January 2026 and 31 May 2026. During this period, the taxpayer may expressly ask their bank to deduct an amount equivalent to this tax and to pay it to the Belgian government.

Taxpayers may also inform their bank that they do not wish to be subject to withholding tax and that they intend to declare their capital gains themselves through their annual personal income tax return. For 2026, this decision must be communicated within the timeframe specified by law (opt-out).

The bank is legally required to provide the tax authorities with a statement of transactions necessary for the authorities to carry out their checks.

10. Is there a specific regime for capital gains on significant interests?

A specific regime applies to capital gains realised by a taxpayer holding at least a 20% stake in a company’s share capital, in respect of significant interests held in all types of company, including a management company or family holding company, with no distinction based on whether the shares are listed or not.

This regime provides an annual exemption for an initial tranche of EUR 1 million in capital gains (amount indexable annually), following which the capital gains are taxable at progressive rates according to the following scale:

Capital gains tax on significant interests is paid via the annual personal income tax return.